1. Field of the Invention
The present invention relates to a scroll type compressor to be applied to a gas-injection type refrigerating cycle in which a part of refrigerant pressure-reduced by a pressure-reducing unit is injected into a compression chamber of the compressor.
2. Description of Related Art
A scroll type compressor applied to a gas-injection type refrigerating cycle is disclosed in Japanese Patent Unexamined Publication No. 62-3184. In this scroll type compressor, an injection port through which a medium pressure refrigerant is injected is formed in a fixed scroll member. The medium pressure refrigerant is injected into a compression chamber via a movable scroll member and the injection port. An injection timing of the medium pressure refrigerant is adjusted by communicating the injection port with the compression chamber intermittently in accordance with an orbit of the movable scroll member.
In a scroll type compressor, a compression reaction force functions on a movable scroll member to separate the movable scroll member away from a fixed scroll member. Thus, in the scroll compressor disclosed in the above reference, a gap arises between both scroll members by this compression reaction force, and the medium pressure refrigerant leaks through this gap to a side of low pressure. As a result, the compressor does not achieve a sufficiently high coefficient of performance.